﻿<p><em>IfcLightDistributionData</em> defines the luminous intensity of a light source given at a particular main plane angle. It is based on some standardized light distribution curves; the <em>MainPlaneAngle</em> is either the</p> 

<ul> 
<li>A angle; if the <em>IfcLightDistributionCurveEnum</em> is set to TYPE_A</li> 
<li>B angle; if the <em>IfcLightDistributionCurveEnum</em> is set to TYPE_B</li> 
<li>C angle; if the <em>IfcLightDistributionCurveEnum</em> is set to TYPE_C</li> 
</ul> 

<p>For each <em>MainPlaneAngle</em> (considered as being the row of a table) a list of <em>SecondaryPlaneAngle'</em>s are given (considered to be the columns of a table). They are either the:</p> 

<ul> 
<li>&#945; angle; if the <em>IfcLightDistributionCurveEnum</em> is set to TYPE_A</li> 
<li>&#946; angle; if the <em>IfcLightDistributionCurveEnum</em> is set to TYPE_B</li> 
<li>&#947; angle; if the <em>IfcLightDistributionCurveEnum</em> is set to TYPE_C</li> 
</ul> 

<p>For each pair of <em>MainPlaneAngle</em> and <em>SecondaryPlaneAngle</em> the <em>LuminousIntensity</em> is provided (the unit is given by the <em>IfcUnitAssignment</em> referring to the LuminousIntensityDistributionUnit, normally cd/klm).</p> 

<blockquote class="history"> 
HISTORY&nbsp; New entity in IFC2x2.
</blockquote>